复合吸附剂CaO/Al2O3对CO2吸附性能的研究-研究生论坛

采用过量浸渍法制备了不同质量分数的复合吸附剂CaO/Al2O3，并采用CO2-TPD、低温氮气吸附脱附、XRD以及FT-IR等方法对吸附剂的结构进行了表征。采用容量法测定了吸附剂在25 oC和70 oC条件下的吸附性能。结果表明，CO2在与吸附剂的作用过程中形成了CaCO3；在吸附温度为70 oC、压力为1.0 MPa的条件下，当CaO的负载量为5wt.%时，复合吸附剂的吸附效果最好，吸附量为36.45 mg/g。用D-R模型计算了复合吸附剂的吸附热，用Clausius-Clapeyron方程研究了复合吸附剂吸附过程的吸附焓变与覆盖度的关系。结果表明，复合吸附剂的吸附热随着CaO掺杂量的增加而增加，而吸附过程的吸附焓变随着吸附质覆盖度的增加而降低。

Study on the Adsorption of Composite Adsorbent CaO/Al2O3 to CO2

CaO/Al2O3 composite adsorbents with various CaO contents were prepared via impregnation method. The structure and surface properties of the adsorbents were characterized by CO2-TPD, XRD, N2 adsorption/desorption and FT-IR techniques. The adsorbent adsorption performance was investigated under different pressures at 25 oC and 70 oC, respectively. The results showed that the composite adsorbents can reacted with CO2 to form calcium carbonate, and the adsorbent 5%CaO/95%Al2O3 had the highest adsorption amount of 36.45 mg/g at 70 oC and 1.0 MPa. Furthermore, the heat of adsorption was calculated by using D-R equation and the enthalpy changes of adsorption against adsorbate surface loading was studied by using Clausius-Clapeyron equation, and it presented that the adsorption heat increased as the CaO content increased, while the enthalpy decreased as the surface loading of the adsorbent increased.